The present invention relates to a new and improved apparatus for use in inflating a vehicle occupant restraint, such as an air bag.
An inflator assembly for inflating an air bag is disclosed in U.S. Pat. No. 3,723,205. This inflator assembly includes a container which holds a gas under pressure. When the air bag is to be inflated, a squib is electrically actuated to ignite a gas generating material. As the gas generating material burns, the pressure in the container is increased due to the gases and heat provided by burning the gas generating material. When a predetermined pressure is reached, a burst disk is ruptured to enable gas to flow from the container to the air bag.
An inflator assembly for inflating an air bag is also disclosed in U.S. patent application Ser. No. 671,947, filed Mar. 19, 1991, now U.S. Pat. No. 5,131,680, entitled "Inflator Assembly" and assigned to the assignee of the present application. Application Ser. No. 671,947 discloses a body of ignitable pyrotechnic material which is disposed within a container in which gas is stored. An igniter assembly is actuatable to ignite the pyrotechnic material. The igniter assembly includes an ignition material which rapidly burns at a relatively high temperature to generate heat and flame which initiate burning of the body of pyrotechnic material.
The aforementioned application discloses an actuator assembly which is operable to actuate the igniter assembly and to rupture a burst disk to release a flow of gas from the container. The actuator assembly includes a pyrotechnic charge which, when ignited, generates pressure against the head end portion of a piston to move the piston. The moving piston ruptures the burst disk and strikes the igniter assembly to ignite the ignition material of the igniter assembly. The ignition material, in turn, ignites the body of pyrotechnic material disposed in the container. As the body of pyrotechnic material in the container burns, flame and hot combustion products enter the container and both heat and supplement the stored gas.